“…In agreement with the well-documented and numerous pro-metastatic functions of EMTs, the detection of certain EMT actors in CTCs has thus been correlated with poor clinical parameters such as an aggressive cancer types and a shortened OS or PFS ( Table 1 ). More particularly, CTCs harboring mesenchymal features have been reported to associate with the presence of metastases in numerous cancers including breast, lung, pancreatic, colorectal, prostate, or hepatocellular cancers [ 101 , 109 , 114 , 116 , 122 , 125 , 169 , 351 , 352 , 353 , 354 ]. Considering particular EMT/CSC molecular actors, studies, for instance, have detected CD44, often in conjunction with other canonical EMT markers, in CTCs isolated from many cancer types, which was associated with poor clinical outcomes in some studies [ 50 , 100 , 170 , 187 , 188 , 335 , 355 , 356 ].…”